Projectile fuze setting apparatus



E. F. CAMPBELL ETAL 2,792,759

PROJECTILE FUZE SETTING APPARATUS 1O Sheets-Sheet 2 May 21, 1957 Filed Dec. 13, 1951 W 1. IO

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PROJECTILE FUZE ss'rmc APPARATUS Filed Dec. 13, 1951 10 Sheets-Sheet 5 HHHHHIMIH ZQQIZM A TTYS.

E. F. CAMPBELL ETAL 2,792,759

PROJECTILE FUZE SETTING APPARATUS May 21, 1957 10 Sheets-Sheet 6 Filed Dec. 13, 1951 INVENTORS ERNEST F. CAMPBELL PHiLIAS HGIROUARD BY ALVIN E. conen .,(Q p, ATTYS.

May2l, 1957 E. F. CAMPBELL EIAL 2,792,759

PROJECTILE FUZE SETTING APPARATUS Filed Dec. 13, 1951 10 Sheets-Shaet 7 INVENTORS ERNEST'F. CAMPBELL PHILIAS H. GIROUARD BY ALVIN E. COHEN y 1, 1957 E. F. CAMPBELL ETAL 2,792,759

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INVENTORS ERNEST E CAMPBELL PHILIAS H. GiROUARD BY ALVIN E. COHEN May 21, 1957 Filed Dec. 13, 1951 600M RECTIFDER E, F. CAMPBELL E'I'AL PROJECTILE FUZE SETTING APPARATUS 10 Shaf s-Sheet 9 CRADLE AMPLIFIER FIG..9.

INVENTORS ERNEST F. CAMPBELL PHILIAS H. GIROUARD BY ALVIN E. COHEN y 21. 1 E. F. CAMPBELL ETAL 2,792,759

PROJECTILEI FUZE SETTING APPARATUS Filed Dec. 13 1951 10 Sheets-Sheet l0 CT-l CT-Z CT-B ISPEED l-SPEED A IBPSPEED 3 GO'VAQ INVENTORS ERNEST F. CAMPBELL PHILIAS H. GIROUARD ALVIN E. COHEN r r rs.

FIGJU.

United States Patent PROJECTILE FUZE SETTING APPARATUS Ernest F. Campbell, Springfield, Va., Philias H. Girouard, Washington, D. C., and Alvin E. Cohen, Chicago, Ill.

Application December 13, 1951, Serial No. 261,572

2 Claims. (Cl. 89-6) (Granted under Title 35, U. 5. Code (1952), see. 266) This invention pertains to a naval type gun turret and more specifically to a new and novel fuze setting control system and to the novel structure and arrangement of parts thereof whereby the handling of the projectile mcrement of the ammunition load is such as to provide fully automatic fuze setting in the cradle assembly of the hoist loading system. This fuze setting during transfer from a hoist position to a transfer position at the gun slide permits more rapid handling and firing of large bore guns than that of large bore guns of similar size heretofore in use. The projectile increment fuze setting equipment and control equipment, therefore, of this invention is well adapted for use with a rapid fire gun and turret arrangement of a type as shown, for example, in the copending application to Philias H. Girouard et al., Serial No. 153,262, filed March 31, 1950. The subject matter of this invention is shown and partially described but not claimed in the above mentioned copending application to Girouard et al.

Heretofore, naval turrets mounting large bore guns have incorporated therein in their apparatus and method of operation the usage of a bag type powder charge for the propulsion of the projectile from the gun. In some smaller bore applications the use of fixed pre packed cased ammunition has been utilized to advantage but in large bore applications such fixed ammunition is extremely heavy and presents some disadvantages in handling. The gun turret system of the type for which this cradle fuze setting arrangement is adapted incorporates the use of semi-fixed ammunition wherein the projectile is handled by a system separate from that of the system handling the powder case. In large bore applications where projectiles have been handled by hoist systems and transferred to a position where they can be manually or otherwise handled for loading into the gun breech, the fuze setting has not been conveniently handled automatically by the control systems therefor while the projectile was in transfer movement, or in a position immediately prior to its movement for transfer.

The guns incorporated in the mount of the turret with which the present invention is associated are well adapted for use with semi-fixed ammunition rather than the powder bag type of ammunition previously used in guns of similar large bore. The incorporation of the semifixed cased ammunition therein as handled by the structural embodiment of this type of turret makes provision for the reception of two load increments, viz., a projectile, and a powder case at positions respectively on each side of the gun slide assembly. Ammunition increments received at the side of the gun slide are loaded into transfer trays of the gun loading system and are thereafter transferred to a firing position in the gun barrel. The projectile increment is stored in a storage chamber below the gun deck and is moved upwardly to a position adjacent the gun slide by a projectile hoist system. The upper portion of the cradle unit is a portion of the hoist and also is an enclosure for the projectile fuze setting system of this invention.

Throughout the transfer movement of the projectile and the powder case the increments follow a predetermined sequence of travel in order that the position of each increment with respect to the other increment be at all times correlated and be such that ramming action applied at the gun barrel to the powder case will also produce ramming movement of the projectile forwardly thereof into the gun breech. In such an arrangement it is essential that any fuze setting operation not delay the sequence or order of the cycle. It is, however, do sirable on occasion to have the fuze setting operation take place at the last possible instant prior to gun firing. Such provision is accomplished by the control system of the turret with which this fuze setting equipment is adapted for use. In such a system, fuze setting may be held up in the cradle and the projectile increment retained until the desired range information is fed into the input of the receiver-regulator of the fuze setter. Immediately after fuze setting takes place, the projectile is released by the ram-spring assembly of the projectile cradle and is ram-ejected into the transfer tray for subsequent transfer to the projectile and powder case aligned-rammingposition rearwardly of the gun breech.

The drive assemblies which move the fuze mechanism of the projectile are enclosed by, and movable with, the projectile cradle and thus can accomplish fuze setting at any position in their path of travel or after the cradle has come to rest in its latched position on the gun slide. The fuze setting receiver-regulator assembly associated with the drive for the fuze setter is also mounted on the projectile cradle for movement therewith. The receiverregulator may advantageously be of the type shown in U. S. Patent 2,444,813, issued July 6, 1948, to F. W. Cunningham. This fuze setting equipment which comprises a fuze setter and a fuze setting receiver-regulator assembly is remotely controlled, and is arranged in a power driven installation embodying an automatic settingpower drive type fuze pot device for use with nose-type mechanical time fuzes. The receiver-regulator embodies an electrical amplifier, an electrical output regulator, and an electric power driving motor.

The fuze setter is mounted within the upper tubular portion of the projectile cradle and has its component sub-assemblies arranged therein in a manner wherein the A-unit or the receiver-regulator is mounted on the for ward side of the cradle and the B-unit or amplifier assembly may be mounted on the bulkhead structure of the gun pocket.

The arrangement of the fuze setter outer housing is such as to serve as a guide for the cradle ram spring of the craddle and encloses the fuze pot assembly, which comprises the holding cup and setting cup associated with the dillerential drive mechanism therefor. All of these component units are separate from the outer housing groups which comprise the drive and gear mechanism, the input coupling and the fuze pot retracting mechanism. The fuze pot retracting mechanism is mounted on the cradle to provide disengagement of the fuze setter in the event that the ammunition being fired is not of a fuze set variety.

One object of the present invention resides in the provision of a fully automatic fuze setting arrangement for setting the fuzes of mechanical fuze-type projectiles and an electrical control system therefor in which many of the foregoing disadvantages are obviated and which is adapted to perform satisfactorily all of the essential functions of the systems heretofore or now in general use, and in which the possibility of mis-sctting fuzes or apparatus malfunction is reduced to a minimum.

An additional object of this invention lies in the provision of a rapid fire rate projectile fuze setter in an arrangement for assembly in the cradle of the gun loading system.

Another object of this invention lies in the provision of a cradle assembly adapted to provide fuze setting at any point along the path of travel of the cradle in its movement from the projectile hoist to the gun slide.

An additional object of this invention lies in the attainment of new and improved fuze setting in a gun loading cycle which is accomplished remotely and by mechanical means without manual intervention.

Another object of the invention lies in the accomplishment by improved means of projectile fuze setting fiiom an information source external to the gun assemb y.

It is an additional object of this invention to provide projectile fuze setting in synchronized time relationship with the loading and handling of a powder case whereby both the powder case and the projectile are available as needed at the gun loading station to maintain uninterrupted operational loading and firing sequence, while preventing premature projectile release prior to the completion of fuze setting.

In correlation with the immediately preceding object regarding simultaneous loading of projectiles and powder case increments, it is an additional object of this invention to provide fuze setting which may be delayed up until the last stage of the gun loading and thus immediately prior to gun firing.

Another object of the invention is the provision of a new and improved control means to permit projectilefuze-setting operations from a location remote from the operating mechanism of the turret and wherein an initial setting of the fuze may be changed after movement to a position at the gun slide to make corrections for changes in the path of travel of the target in the event some delay exists between the time of projectile cradle movement and the instant when gun firing is desired, while maintaining a constant dead time therefor.

Additional objects and advantages of this invention will be apparent from the following decription of a preferred embodiment and the same will be readily appreciated as they become better understood by reference to the following detailed description of the preferred embodiment of the instant invention and the accompanying drawings wherein:

Fig. 1 is a generally schematic diagram of the fuze setting control circuit and shows the component control assemblies thereof;

Fig. 2 is a fragmentary view partially in section showing the upper cradle arrangement for the mounting of the fuze setter and showing further the manner in which the fuze pot is adapted for engagement with a nose type projectile fuze;

Fig. 3 is a fragmentary view partially in section showing the drive gearing arrangement for the fuze pot;

Fig. 4 is a partially fragmentary View showing the fuze setter retractor mechanism and the means of operating it from equipment associated with and mounted on the projectile cradle;

Fig. 5 is a view showing the general arrangement of the fuze setter receiver-regulator unit as assembled in a gun turret for use therewith;

Fig. 6 is a generally schematic diagram of the gearing arrangement of the fuze setting equipment;

Fig. 7 is a schematic wiring diagram of the fuze setting receiver-regulator amplifier;

Fig. 8 is a schematic wiring diagram of the electrical system and showing certain assemblies thereof in block form, with the switch circuit thereof set in Run position;

Fig. 9 is an operational diagram of the fuze setting equipment cycle and shows the functional purpose of the various elements of the assembly and their associated relationship with all of the other elements, and

Fig. 10 is a schematic wiring diagram of the complete electrical circuit of the fuze setting system.

The mechanical-time fuze for which the apparatus of the instant invention is intended is illustrated generally in Fig. 2 wherein the projectile is shown at 12. The nose portion at 7 is rotatable with respect thereto, and is provided with a notch for reception of pawl 16 of the setting cup. The rotatable fuze portion includes the time calibrations shown in the drawing while the fixed part is that portion therebelow. The fixed part includes a recessed notch or the like for reception of the holding dog or pawl at 14. The internal construction is such that rotation of the nose portion 7, with respect to the fixed part on the projectile, through an angle representing fuze order produces the desired time setting.

Referring now to Fig. 1 of the drawings, the fuze setting receiver-regulator shown generally at 1 is mounted on a rear portion of the projectile hoist cradle assembly 2, for movement therewith from a cradle loading position at the hoist to a cradle discharge position at the gun slide for ejection of the projectile into transfer trays of the gun system. The cradle is pivotally mounted by suitable trunnions at 4 to provide this movement. The fuze pot assembly which is adapted to engage the projectile is shown at 5 and is arranged with a retracting mechanism 6 for engagement with the nose 7 of the projectile 12 or for disengagement from the projectile in the event the projectile increment to be fired is not of a fuze-set variety. The arrangement of Fig. 1 additionally includes a regulator amplifier 9. The entire system is associated with the gun captains control panel 8 and the turret oificers transfer switchboard 11.

Referring now to Fig. 2 of the drawings the projectile is shown at 12 in engaged relationship with the projectile guide cup 13 which is a part of the projectile cradle. Adjacent thereto is a rotatable fuze holding cup 3 wherein, the fuze holding slot of the fuze, is engaged by a holding dog 14 thereof. The fuze setting cup 15 is provided with a setting dog 16 for engagement with the rotatable portion of the projectile fuze. The setting cup 15 is a rotatable assembly suitably mounted by bearings 55, Fig. 3, and 18, Fig. 2. The fuze holding cup assembly 3 which carries the holding dog 14, is suit ably mounted on bearings 17 and 20. Bearing 20 is mounted in the fuze setter head 3 and serves as a support for bearings 18. Seals 19 and 21 are provided for the purpose of limiting oil leakage from the differential drive assembly associated therewith. The positioning device 22 is arranged interiorly of the ram or ejection spring 23 of the cradle. It is mounted on the projectile guide cup 13, in a manner to maintain the fuze setter in contact with projectiles of various lengths, and functions to position the guide cup 13 in axial relation to the fuze holding cup 3. The fuze setting cups and the dog elements associated therewith are driven from a power source 10 in the receiver-regulator by power applied through a coupling 24 which comprises the coupling hub 25, a coupling disc, and an upper coupling hub 26 of Fig. 3.

The coupling is spline-shaft mounted to the input gear 27 which is suitably mounted by bearing elements 28 for rotation in the gear case 29. An idler gear 30 is suitably mounted on a bearing assembly 31 for engagement with the driving gear 32. This driving gear is mounted between parallel ball bearing assemblies 33 and 34 and is arranged to drive an internal spur gear hub 35 having a sliding spur gear 36 arranged therewith. The sliding spur gear 36 is mounted on the shaft 35 by means of a key 37 in the keyway 38 and a loclcnut at 39, and is arranged at its opposite end to be rotatably mounted in the bearings 40. Near the lower end of the shaft, there is a pinion at 41 to rotate the ring gear 42 which is in engagement therewith and adapted on. its inner surface to receive and support a pair of lower spider bevel gear elements 43 and 44. The bevel gears are arranged in an assembly to engage and drive the lower bevel gear member 45, Figs. 3 and 6, which is an integral part of the holding cup assembly 3. An intermediate bevel gear 53 is a double gear, having one gear 46 thereof arranged to engage the opposite surfaces of the small bevel gears associated with the ring gear and is mounted in a parallel arrangement with respect to the lower bevel gear of the holding cup. The rotatable mounting for the spider bevel gears 43 and 44 is provided by a shaft and bearing assembly located at one side of 47. The intermediate bevel gear 53 is arranged to drive a pair of fixed bevel gears 48 and 49 which are rotatably mounted in a fixed position by means of the bearing assembly 50 which is arranged to receive the stub shafts 51 and 52 (not shown) of these fixed bevel gears. The fixed bevel gears which are driven by the intermediate bevel gear 53 are arranged to prevent unit rotation of the differential assembly and to impart rotation to the upper bevel gear 54 which in turn is mounted for rotation in the bearing 55 and is arranged to drive the setting cup drive 56 of the assembly. The drive is provided through a shaft and hub assembly 57 of Fig. 6 which is arranged internally of the bevel gears and the intermediate bevel gear 53 and extends downwardly to the upper end of the setting cup assembly 15.

A bayonet joint 58 is provided in the upper fuze pot housing cover 59 for reception of the retract shaft 60 of the fuze pot retractor assembly 6. This retract shaft may be enclosed by a fuze pot tension spring 61. It is arranged to extend upwardly through a support mounting 62. Alternatively, the preferred embodiment incorporates a pair of springs 61 spaced on each side of the shaft 60. One of these springs 61 is shown behind the shaft 60 in Figs. 3 and 4. The linkage assembly for retracting the fuze pot is as shown in Fig. 2 and Fig. 4 and includes a link shaft 63 connected to the retract shaft pivot 64. The link shaft 63 is pivotally connected at 65 to a bell crank 66.

The bell crank is mounted on the support structure 67 of the cradle 2 and is connected at the opposite end thereof to a handle driven sliding yoke link 68 which in turn is pivotally connected at 69 to the pivotally mounted handle 70. The handle is mounted on the upper frame structure of the cradle and is pivotally mounted at 71 by a pin 72 which extends through the lower portion of the handle 6. This handle-lever arrangement is provided with a detent at 73, not shown, for the purpose of maintaining the handle in a locked or in lockedout position for the fuze pot.

The fuze pot drive assembly at 1, Fig. 2, which drives the differential gear assembly for holding and setting the fuze is preferably constructed as a separate unit and is arranged to have the output shaft 74 thereof of Fig. 6 arranged for engagement with the coupling hub 25 of the gear drive assembly. As shown in the schematic diagrams of Fig. 1 this output shaft of the fuze setter receiver-regulator serves as the input to the gear train for the fuze pot.

Referring now to Fig. 6 the fuze setter receiver-regulator comprises a regulating drive system, an indexing drive system and an output drive system which cooperate to provide an output through shaft 74. In addition to these drive systems the gearing illustration includes a showing of the fuze setter input drive which is connected to shaft 74 by coupling 24, as hereinabove described. The regulating drive is placed in operation by means of a regulating motor 75 having a spur gear 76 mounted on the shaft extension 77 thereof. This spur gear is arranged to drive the pinion gear 78 which in turn is coupled by the shaft 79 thereof to a spur gear 80 and to a bevel gear 81. The spur gear 80 is arranged to drive its mating gear 82 and provide output energy for the output drive element. Control of the output regulating drive is provided by a control transformer 83 having its shaft 84 arranged with a gear 85 thereon and in engage ment with a gear 86 which is driven by the bevel gear 87 through shaft 88. The upper end of shaft 89 is provided with a bevel gear 90 for mating engagement V 6 with the bevel gear 81 of shaft 79. The control also includes a velocity dampening generator 91 arranged to be driven by gear 92 through gear 78 to the shaft 93 thereof.

The indexing drive assembly generally designated 94 for positioning the fuze holding cup and its dog initially prior to fuze setting is controlled by the indexing motor 95 having a clutch assembly 96 connected to the output shaft 97 thereof. This clutch is arranged to drive through the disc 98 to the driven disc 99 of shaft 100 which has a gear 101 on the output end thereof. A brake shoe 172 and a brake member 173 are arranged for engagement with the driven disc 99 of the clutch 96. The

motor output gear 101 is connected in engaged relation ship with a gear 102 to drive a gear 103 of the shaft 104 and is additionally arranged with a pinion 105 on a shaft 106 thereof for engagement with a gear 107, which in turn drives through a train of gears 108 and 109 to a shaft 110 on which are mounted the indexing cam 111 and the brake cam 112. These cam members are arranged in a manner to operate a brake auxiliary switch 113 and an indexing switch 114 of the control system for the unit.

The shaft 104 which is driven by gear 103 has a bevel gear 115 mounted on one end thereof for engagement with a differential bevel gear assembly at 116. This differential assembly is arranged to drive the output drive, and as hereinabove set forth is driven by the regulating drive through gear 82 of shaft 117, and the bevel gear 118 as well as by the indexing drive 94 through the above recited bevel gear 115.

The output of the system which drives the adjustable coupling 24 and which receives drive energy imparted by either the regulating drive at 82 and 116 or the indexing drive at 103 through the differential 116 is arranged with a shaft 119 connected to the spider of the difierential unit and to a gear 120. Gear 120 is arranged to drive through an idler gear 121 to the output gear 122 of shaft 74 for the adjustable coupling 24. The shaft 119 on which the gear 120 is mounted, additionally includes a pair of spur gears 123 and 124 on the shaft thereof. The gear 123 is arranged to drive through gear 125 to the shaft 126 of a control transformer 127. The gear 123 additionally drives the pinion 128 to impart rotation through the shaft 129 to a bevel gear 130 of the right angle gear assembly at 131. This gear assem bly drives through its shaft 132 the bevel gear 133 and the bevel gear pair 134 and 135. The bevel gear 134 is arranged to drive the high speed check dial 136 by means of a gear assembly 137 and shaft 138. The bevel gear which is also driven by bevel gear 133 has a worm 139 and worm wheel 140 arrangement to drive the low speed check dial 141 and the minimum fuze setting cam 142 mounted on the output of the shaft 143 thereof. This cam is arranged to engage the minimum fuze setting switch 144. The gear 124 on shaft 119 is arranged to drive through an idler gear 145 to a gear 146 of the control transformer 147.

The operational arrangement of the schematic system as hereinabove described is set forth for purposes of illustration but is not necessarily limited to the particular gear and shaft arrangement illustrated in Fig. 6. The arrangement of the fuze setter elements as hereinabove described is such that the fuze setter outer housing serves as a guide for the cradle ram spring 23, Fig. 2, and encloses the fuze pot assembly 5. The fuze pot assembly comprises the holding cup, at setting cup and a differential drive mechanism. All other components comprising, the driving gear mechanism, the input coupling, the fuze pot retracting mechanism and the inner lock switches, are separate from the outer housing group and are mounted on the cradle bracket.

The A-unit Fig. 5 of the regulator 1 is a water-tight case enclosure with its interior components arranged in a chassis type assembled relationship with three access covers at 148, 149 and 150. They comprise the terminal tube access 148 in the front, a terminal block and drain access-149 in the bottom and a main access cover and a dial window forming the back 150. The main chassis 151 of the unit supports the indexing motor, the dial assembly, the differential 116, the minimum fuze setting cam and switch, and a portion of the instrument gearing. The interior details not shown include a sub-chassis and a lower chassis. The sub-chassis therein is mounted on the rear of the main chassis and provides a mounting for the regulating motor, the synchro control transformers, the velocity damping generator, the indexing and brake auxiliary cams, and the indexing and brake auxiliary switches. These main units of the receiverregulator for operation of the fuze setter are hereinafter designated as the A-unit 1, which is the unit mounted on the forward side of the projectile cradle, and the B-unit or amplifier 9, Fig. 1 the assembly of which is mounted on structure of the gun pocket. The B-unit comprises an amplifier cabinet having therein a blower on motor M-3, Fig. 10, for cooling the chassis assembly units thereof.

The equipment of the A-unit main chassis group comprises the indexing motor 95 with the input magnetic clutch and brake elements at 96, the instrumentation gear mechanisms, the check dials 136, 141 and the minimum fuze setting cam and switch assembly 144. These elements are shown in block diagram form in Fig. l and with their power source interconnections, while the operational relationships therefor are illustrated in the gearing diagram of Fig. 6.

The general system for the electrical interconnections between the elements of the fuze setting equipment and the control switches of the gun captains control panel is shown in Fig. l. The several power supply sources are also indicated thereon. The system includes two external power supply sources, wherein the main power supply is 440-volts, 3-phase, 60-cycle current from the projectile hoist power controller, and the synchro supply is 115-volts, single'phase, 60-cycle current. These service currents are transformed and rectified for motor and amplifier supply by the transformer and vacuum tube rectifier units of the receiver-regulator system.

The fuze pot housing assembly which is enclosed by the cradle is retracted from the projectile engaging position by the linkage 63, 66, 68 connecting the retract handle 6 with the retract shaft 60, Fig. 3. The retract shaft slides in the fuze setter switch mounting bracket 62 and is connected to the fuze pot housing covered by the bayonet joint 58 as shown in Fig. 4. An O-ring 152 is mounted in the switch bracket to seal the retract shaft. As hereinbefore described, one end of the connecting linkage is secured to the end of the retract shaft 60 at 64, and the opposite end of the link is secured at 65 to one arm of the bell crank lever 66, which is mounted on the pivot pin 67 on the cradle bracket. An adjustable slotted clevice rod 68 connects the other arm of the bell crank lever 66 with a retract handle 6 on the upper flange 71 of the cradle bracket. The retract handle is pivotally mounted at 72 on the handle bracket whereby it may be locked either in the retracted position or in the normally extended position. This locking action is accomplished by a detent 153 which is a part of the handle knob 154. Detent holes are provided at 155 and 156 in the handle bracket for engagement by the detent when the handle is moved to the desired position.

The fuze pot housing is fully retracted when the retract handle is located in its upward position. Provision has been made for adjusting the retract mechanism by increasing or decreasing the effective length of the slotted clevice rod 68, by turning the rod into, or out of the clevice 157 that is pinned to the retract handle at 69. The slotted clevis 68 permits the retract handle to be locked at the in" position while permitting the fuze setter head to be at variable distances of its movement.

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8'. This also permits thezfuze setter. head to translate when contacted by the projectile.

A pair of fuze setter regulator interlock switches are mountedin the assembly as shown at 158 on a switch mounting bracket 62 which additionally serves as a guide for the retract shaft as shown in Fig. 4. The switch housing encases two sets of single-pole, double-throw contacts, which switches are controlled by the retraction or translation of the fuze pot assembly in the cradle. Two of the contacts of switches BZ-l, and BZ-Z of Fig. 10 are closed when the fuze pot housing is in its normally extended position, and the other two contacts are closed when the fuze pot housing has been translated by loading a projectile into the cradle. The switch plunger 159 is actuated by a pivoted, spring-loaded, switch lever 160 mounted below the switch on the switch mounting bracket 62. The taper at 161 is provided on the end of the retract shaft 60 to provide movement of the switch lever upwardly when the fuze pot housing is translated. The switch lever is spring returned when the fuze pot housing moves to its normally extended position and the portion engaging the taper drops to a reduced diameter section of the retract shaft.

The fuze setter is controlled from the gun captains control panel by the fuze-setter regulator control switch which is a manually operated, 3-position, rotary type switch. This switch is provided for the purpose of energizing and deenergizing the fuze setter regulator control circuit as hereinafter set forth in greater detail.

When the switch is turned to a run position thereof, it functions to close the l15-volt, single-phase, 60-cycle projectile hoist supply to the relay BER-3, Fig. 8. This closes contacts to connect the rectifier circuit for the indexing motor 95, the safe signal transformer 163 and the blower motor of the amplifier, to the 440 volt, 3- phase, 60-cycle, projectile hoist supply. In the run position thereof, this switch also connects the l15-volt synchro circuit to apply it to the regulator safety circuit, the primary of the generator field supply transformer T-8 of Fig. 10 and the bias circuit in the main field of the regulating motor. Additionally this switch when at its run position also connects the low and high-speed fuze setting order input for the stators of the control transformers with the plotting room source therefor.

A second position of the switch is a safe position, which functions when the selector switch is turned thereto to disconnect the incoming fuze setting orders from the plotting room, and connect the stators of the control transformers with a fixed signal. This is termed the safe signal, and it is derived from a safe signal transformer T-6 which drives the fuze to a safe position.

In the off position thereof the switch cuts out signal transmission to the fuze setting recciverregulator and closes an additional circuit through GS-l and -2 of Fig. 10 to bypass the fuze setting system in controlling projectile release from the cradle.

The indexing motor in the regulator functions to rotate the dogs or pawls in the fuze setter far enough to insure their positive engagement in the slots in the projectile fuze. This action takes place immediately after the projectile enters the fuze pot. The mounted arrangement thereof in the main chassis of the A-unit is as illustrated in Fig. l. The motor is a constant-speed, non reversible, fractional horse-power design operating on the 440-volt, 3-phase, GO-cycle current from the projectile hoist supply. The moto ris designed to run continuously in the direction to decrease the fuze setting time whenever the selector switch BW on the gun captains control panel is turned to run" or safe position. This motor operates theindexing drive of the fuze setter as hereinbefore stated to provide three dead turns of the fuze setter cup in order that the dogs thereof will be positively engaged for any initial dog position with respect to theslots in the .projectilenose when a mechanical time-fuzed projectile is seated therein by the cradle ram. After the completion of three revolutions of the cup, the magnetic clutch 96 functions to disconnect the motor 95 from the indexing drive 94. Thereupon the magnetic brake disc surface 172 stops rotation of the indexing drive shaft 104 and consequently the application of power from this source to the differential 116. Other units of the fuze setting equipment thereupon take over performance of fuze setting operations.

A magnetic clutch and brake assembly 96 is mounted between the indexing drive motor 95 and the indexing drive 94. The operative arrangement thereof is as indicated diagrammatically in Fig. 6. The clutch and brake assembly consists of a friction brake ring 172, a friction clutch disc 98, a friction drive disc 99, a magnetic clutch coil at 171 and a magnetic brake coil 173. The magnetic clutch coil is secured to the shaft extension end of the motor housing. The friction drive disc 98 is secured to the indexing motor shaft and is turned by the indexing motor. The friction clutch disc 99 is secured to the output shaft 100 of the indexing drive and provides ro tational energy for this shaft. The friction brake ring 172 is attached to the magnetic brake assembly which surrounds the indexing drive shaft and is secured to the brake coil housing assembly at the end of the housing. The indexing drive is that portion of the instrument shaft and gearing assembly which connects the indexing motor 95 with one end gear of the differential gear 115. The indexing drive functions to turn the fuze setter cups the necessary three dead turns to assure positive engagement of the fuze setting pawls in the slots of the differential fuze.

One end of differential 116 is supported on the main chassis 151, while the other end of the differential bracket is secured to the lower chassis. The differential 116 is mounted in such a manner that one end gear 118 of the differential is driven by the regulating motor 75, while the opposite gear 115 of the differential is driven by the indexing motor 95. The spider, or output shaft of the differential drives the fuze setter and the control transformers 147 and 127. The output shaft also drives the check dials and the minimum fuze setting cam 142 which operates the minimum fuze setting switch 144. The differential output, or spider shaft rotations of the differential produce the algebraic sum speed of the differential end gear inputs respectively from the regulating motor and from the indexing motor. During indexing operations the output of the regulating motor, which represents fuze setting order, is combined with the output of the indexing motor, representing the dead turns in a manner whereby the fuze setting corresponds to the fuze setting order at the completion of the dead turns. Subsequently, the output from the indexing motor is locked by means of the magnetic brake, and the differential output to the fuze setter is directly proportional to the regulating motor output. Thus the fuze is continuously maintained in synchronism with the fuze setting order until such time as the projectile is ejected from the cradle.

Two check dials 136 and 141 are geared to the receiver-regulator output drive and serve to indicate the fuze setting order in seconds of time. Their mounting arrangement in the instrument is such as to make them visible from the back portion of the fuze setter housing or forward with respect to the gun. The low speed check dial 141 is mounted on the minimum fuze setting cam 142 at the left side of the case of the A-unit. This dial is calibrated from to 45 seconds in units of 0.2-second divisions. It is numbered at 0 and every 2 second interval from 1 to 45 inclusive; that is, 0, l, 3, 5, 7, etc. to 45 seconds. The dial is arranged to have an S or safe indication at the safe position thereof. The high speed check dial designated as 136 is mounted to the right of the low speed dial and is engraved with a single crowfoot index mark. A lubberline is inscribed on. an index dial plate between the two check dials. At

the electrical zero position of the output drive, the crowfoot index mark on the high speed dial is in alignment with the 10 second mark on the low speed dial and both marks are aligned with the lubberline.

The minimum fuze setting cam 142 hereinafter diagrammatically designated as CA-Z is mounted on the output drive at a position adjacent to the minimum fuze setting switch 144, schematically referenced SW-4 and is turned at low speed by the output drive and functions to control the operation of the minimum fuze setting switch. The switch 144 functions in connection with the regulator safety circuit to prevent the release of the projectile at any time when the rotational position of the output drive shaft is below a predetermined safe minimum fuze setting value. The minimum fuze setting switch is bracket mounted on a chassis assembly at a position directly below the low speed check dial 141. A roller 174 on the switch plunger is in alignment with the cam and arranged in a manner to be actuated by following the contour changes of the minimum fuze setting cam.

The regulating motor 75 serves as the fuze setting time control motor and is a reversible, variable-speed, fractional horsepower, two-phase induction type wherein one phase is connected to the volt alternating current synchro supply and the other phase is connected to the output from the amplifier. The motor is arranged to provide operational output whenever the selector switch BW on the gun captains control panel is turned to "run" or safe position. This motor is controlled by the error between the fuze setting order and the response from the regulator output shaft to the fuze setter. It functions to operate the regulating drive and maintain the angular displacement between the fuze setting dogs in synchronism with the incoming signal. The hereinbefore recited regulating drive is that portion of the instrument shaft and gearing which connects the regulating motor with one end gear 118 of the differential 116 as well as with velocity dampening generator 91 and the rotor of the control transformer 83. This regulating drive provides the function of maintaining the angular displacement of the fuze setter pulse in synchronism with the incoming synchro-signal. This arrangement is such as to provide both coarse and fine control and is adapted to operate with or without a projectile in the fuze pot.

The fuze setting system incorporates three synchro control transformers 147, 83, and 127 which function to control fuze setting through reception by the stators thereof of a synchro transmitted electrical fuze setting order wherein the rotors of the control transformers are driven by the output response of the regulating motor. The units function in such a manner that any difference between the position of the fuze setter drive and the signal received by the regulator produces an error voltage in the rotors of the control transformer. This error voltage is applied to the amplifier where it is amplified to a raised power level. Thereafter the amplifier output is applied to the control winding of the regulating motor in accordance with the fuze setting order.

The assembly also includes a velocity dampening generator 91 which is shown in the schematic diagram of Fig. 6 and which is mounted within the receiver-regulator case as shown generally in Fig. 1. This unit is driven by the regulating motor 75 and is arranged to introduce a dampening voltage into the signal circuit. This dampening voltage when applied to the amplifier with the error voltage, is proportional to the speed of the generator and opposes the error voltage. The dampening voltage tcnds to eliminate oscillation and overshooting and to cause smooth follow-up action. The velocity dampening generator is preferably a low-inertia, cup type induction device having both the main or exciting winding and the control field wound on the stationary stator. The bearing supported, cup type rotor encircles the sta- 11 tor. Both the rotor unit and the startor are cased within the generator housing.

In the operative relationship thereof the main field is excited by current flow from the generator field transformer shown schematically as T-8, to produce a resultant magnetic field which causes circulating currents to be set up in the rotor. These currents, in turn, produce a voltage in the control field of the generator which is proportional to the speed of the rotor. This voltage which is proportional to the rotor speed is utilized as the dampening voltage.

The indexing and brake auxiliary cams respectively designated CA-l, and CIA-1A in Fig. 8, are mounted in spaced adjacency on the indexing drive cam shaft and in a manner wherein each respectively is separately and independently adjustable. The indexing cam and switch assembly at 111 coact with the brake auxiliary cam and switch assembly at 112 to control the indexing drive cycle by regulating the action of the magnetic clutch 96 and the magnetic brake coil 173. The switches associated with the indexing and brake auxiliary cams are provided with rollers 174, Fig. 6, which are aligned with and actuated by the contours of the respective cams.

The circuitry of the magnetic brake coil winding includes two resistances shown at R-49 and R-SO of the electrical circuit schematic drawing Fig. 10. The resistor R-49 is a coil resistor for the magnetic brake BM-l, and functions to limit the current to the coil 173 thereof to a normal amount required for brake operation. The resistor R50 is used in the circuit to limit the brake current to a subnormal value which is insufficient to allow operation of the brake prior to the completion of the cycle. This arrangement allows quick brake application when the indexing cycle is completed.

The showing of the electrical circuitry additionally includes the blower motor designated schematically as M-3, used for dissipating heat from the amplifier, but which is not to be construed as an essential element of the inventive concept. It is a constant-speed, non-reversible, fractional horsepower unit mounted in the amplifier case to operate from the 440-volt, 3-phase, 60-cycle current source supplied by the projectile hoist power supply or any other suitable external power supply source. This motor is arranged in the circuit in a manner whereby it is designed to run continuously at all times when the selector switch BW, located on the gun captains control panel, is turned either to the run or the safe position. It is directly controlled by action of relay BER-3, through energization of the relay by the positioning of switch BW. This motor is connected to drive a squirrel-cage type blower unit for providing air circulation as a coolant for the elements mounted within the B- unit case.

The resistors R-46, R-47, and R-48 of the electrical schematic diagram comprise the impedance network of Fig. 10. They are strip heaters which are mounted within the amplifier case and function as regulating motor reactor resistors.

In the hereinafter described electrical circuit of Fig. conventional designations are used wherein the prefix V indicates vacuum tubes, the prefix T transformers, C condensers, R resistors and CH chokes. Potentiometers used in the circuit are indicated by the prefix designation P.

in the hereinafter set forth description the connected relationship of all other electrical system components is set forth in a general manner only; the particular circuit terminal connections thereof being obvious to one skilled in the art, since it requires the mere following through of the line connections of the diagram. The vacuum tubes incorporated in the several circuits are thirteen in number and are designated as V1 to V-lS respectively. Vacuum tubes "v and V4 are connected to the low speed signal circuit, wherein Vl is a pentode type of a commercial variety designated as a 6517, and the tube V-Z is a twin-triode type similar to the commercial 6SN7 type. These two tubes are controlled by the coarse control error voltage and function to regulate the operation of the speed transfer relay designated RVY-1.

The vacuum tubes V-3 and V-4 of the circuit are connected to the high speed signal circuit in a manner whereby the fine-control error voltage controls the functioning of the tubes, and the tubes in turn regulate the operation of the synchronizing relay RVY-Z. Similarly as tube V-l. the tube V-3 is a pentode type of the comiilaluilll 3;..57 variety while tube V-4 like tube V-Z is a twin triode of the type commercially designated as a 6SN7. These two sets of tubes function in a similar capacity in their respective vacuum tube relay systems hereinafter described in greater detail.

Vacuum tube V-S is used as a class A voltage amplifier in a manner whereby it functions as the first stage of amplification of a four stage high gain amplifier. It is a pentode type commercially designated as a 6517. The tube operates in conjunction with the other tubes in the amplifier to supply control voltage of the primary of the driver transformer T-2 for control of the regulating motor 75. The twin-triode type tube V-6 is of the commercial type 6SL7 and functions as the second tube stage of amplification of the amplifier circuit wherein the service thereof is as a phase inverter to the pushpull stage therefollowing. The connection of this tube is such that the tube operates as two independent triodes enclose in the same envelope.

A pair of beam power pentode-type output tubes V-7 and V-S of the commercial 6V6 variety are connected in the amplifier circuit to form the third stage of amplification. They function as class ABi push-pull amplifiers to supply the final push-pull stage of amplification. The final stage of amplification incorporates a pair of power tubes V-9 and V-IO of the 811 variety which operate at a high power level as class B push-pull amplitiers to serve as the fourth or final output stage of amplification.

The power supply circuit of the amplifier incorporates the vacuum tube V-ll as a full-wave vacuum tube rectiher. This tube which is of the commercial type 5R4GY type is connected with the rectifier transformer T-3 to supply the required voltages to the tubes. It rectifies the alternating current of the proper stepup secondary voltage, which is applied through the transformer from the 440-volt, S-phase, -cycle projectile hoist supply therefor. The tube output supplies the 600 volt direct current plate circuit for the amplifier.

The 300 volt direct current plate supply for the amplifier is supplied through vacuum tube V-lZ which also is a full-wave vacuum type of the 5R4GY commercial variety. It is supplied through transformer T-4 which in turn has the primary thereof connected to the 440- volt, 3-phase, 60-cycle supply.

Similarly, vacuum tube V-13 is of the 5R4GY fullwave type and is connected to rectifier transformer T5 from a similar power source. This tube supplies the 230 volt directcurrcnt supply for the indexing drive control circuit.

In addition to the hereinabove recited transformers T-3, T4, and T-S the circuit includes transformer T-l which serves as an interstage driver transformer and the transformer T-Z which is an output transformer.

The interstage transformer T-1 functions as a coupling transformer for connection between the third and fourth stages of the amplifier; the primary thereof is energized by the push-pull third stage and induces a voltage in the secondary thereof to control the grids of the push-pull fourth power stage.

The primary of the output transformer T-2 is supplied by the push-pull fourth stage and functions to energize the control field of the regulating motor.

The transformer T4 functions as a rectifier transformer operating through connections to the plates of the vacuum tube rectifier V12, to supply the necessary 13 potential to the plates and filaments of the vacuum tube rectifier. An additional secondary thereof supplies in a conventional manner the filament current for the vacuum tubes of the amplifier and the vacuum tube relays.

Rectifier step-up transformer T-3 has the primary side thereof connected to the 440-volt, I i-phase, 60-cycle supply. Its secondary windings are connected to the plates of the 600-volt vacuum tube rectifier V-ll. A second secondary thereof is connected as shown in Fig. 10 of the schematic diagrams to the cathodes of the rectifier tube therefor in a manner to supply the necessary potential to the plates and cathodes of the vacuum tube rectifier.

Transformer T-S similarly is a rectifier transformer adapted for connection to the same power source. One secondary thereof is connected to the plates of the 230- volt vacuum tube rectifier V-13. The second secondary connection is connected to the filamentary cathodes, of the same tube. The transformer thus functions to sup ply the necessary potential for rectification across the plates and cathodes of this vacuum tube rectifier.

The transformer T-6 is a safe signal transformer; the primary side of which is connected by two leads to one phase of the same power source as the hereinabove recited transformers. The secondary side thereof is connected to the safe terminals on the selector switch BW of the gun captains control panel shown in Figs. 9 and 10. The transformer functions to impress a fixed voltage of approximately 90 volts, for example, as a safe signal on the stators of the three control transformers whenever the switch is turned to safe position. As the result of the action of this transformer a fixed voltage is induced in the rotors of the synchro control transformers causing the regulating motor to drive the output shaft and consequently the fuze setter, to set the projectile to safe. Additionally the transformer energizes the primary of transformer T-8, the CT bias circuit, the field of regulating motor M-l, and the regulating safety circuit when switch BW is in safe position.

Transformer T-7 is the CT bias transformer, hereinbeforc made of reference. The primary side thereof is connected through a resistance network and a condenser to the iii-volt synchro supply. The secondary thereof is connected to the rotor windings of the synchro control transformer CT-l. This transformer functions to supply a small constant alternating-current bias voltage to the control transformer of the required phase to prevent the possibility of false synchronization.

Transformer T-8 serves as the generator field supply transformer with the primary side thereof connected to the l15-volt synchro supply as is transformer T-7. The secondary thereof is connected to the generator field of the velocity generator 6-1. This transformer functions to step-down the lli-volt synchro supply to 25-volts for the field supply of the velocity dampening generator 91.

Choke CH-l is connected in series with condenser C- 21 across the output of the GOO-volt direct current rectifier tube V-lI as illustrated in the schematic diagram of Fig. 10. This choke, acting in conjunction with the condenser C-Zl, functions to filter the rectified alternatingcurrent voltage and minimize ripple in the direct current supply to the amplifier.

Choke CH-Z is connected in series with the rectified SOD-volt direct-current output in an inductance-input filter network incorporating filter condenser -22 and C-23 which are connected across the rectifier output. This direct current rectifier filter arrangement is conventional and functions in a well-known manner to smooth out ripple occurring in the rectified voltage and thereby pro duce a more uniform direct-current output.

The potentiometer P-l is a gain control potentiometer which is connected between the first and second stage of amplification to provide controlled increase or decrease in the sensitivity of the amplifier by manual adjustment thereof.

The potentiometer indicated at P-2 is a signal control potentiometer connected in the amplifier circuit in a manner to control the signal input voltage thereto. Similarly as Pl, it is provided with a manual adjustment which facilitates voltage adjustments for increase or decrease of signal control. This control is such that with an increase in the signal control voltage the effect produced is that of reducing the velocity dampening voltage to decrease dampening action.

The condensers C-1 and C-2 of Fig. 10 are connected respectively in parallel with the relay coils of the vacuum tube relay systems RVY-1 and RVY-Z. They function to filter the pulsating current flowing through the relay windings in a manner to produce a more uniform voltage across the relays and prevent any possibility of contact chattering. Condenser 0-3 is an element of the amplifier circuit wherein it is connected in the first stage of amplification thereof from ground to cathode of vacuum tube V-5. It serves as a shunt by-pass across the cathode resistor R22 to shunt the alternating-current component of the plate current of this vacuum tube so that variation in plate current will not effect the potential on the tube cathode. The condenser C4, shown in the amplifier schematic, is connected between the plate of tube V-5 and ground wherein it by-passes high frequency signals to prevent high frequency oscillations in the circuit.

Condenser C-S, Fig. 7, is connected to ground the resistance-capacitance filter network between the first and second stages of amplification. It functions in conjunction with this network to produce a required phase shift of the first stage output voltage as well as the function of filtering the third harmonic of the 60 cycle signal.

The screen grid by-pass condenser C-6, Fig. 7, is connected to the screen grid of tube V-S of the amplifier circuit and in series with condenser C-3 in a manner to maintain equal potential between the cathode and the screen grid, and to prevent oscillations in the circuit.

The coupling condenser (3-7 is connected between the output of tube V-S and the input of the second stage at tube V-G. It precedes the filter network and passes the alternating-current component or output of the first stage to the second stage, and additionally prevents the passing of direct current plate potential to the grid of the second stage.

The resistance-capacitance filter network includes the condensers C-8 and (3-9 between the first and second stages of the amplifier. They function as a part of the phase shifting-filter network therefor.

The condenser C-Ill which is connected between the plate and grid of one section of the dual triode vacuum tube V-6 in the second stage of amplification helps to produce a negative feedback, which while slightly reducing the gain of the second stage acts to suppress oscillation therein and reduce harmonics in its output. The condenser C-ll of the amplifier circuit is connected between the plate of the hereinbefore described section of the dual triode V-6 with the connection thereof between the plate and ground in a manner to shunt high frequency harmonics from plate-to-ground.

The coupling condenser (1-12 functions in a manner similar to coupling condenser C-7 to pass the amplified signal from the tube V-6 to the grid input of tube V'-7, and to insulate the grid from direct-current potential. The output of the second section of the dual triode V6 is coupled to condenser 0-13, Fig. 7, similarly as the first section is coupled through condenser C-12 to the grid of the beam power tube V-8. The condensers 0-14 and C-15 are connected in the primary circuit of the interstage transformer T1 wherein they function to keep the amplifier stable by by-passing high frequencies from the transformer.

Condensers C-16 and C-17 in the primary of the output transformer T-2 are connected in parallel to the transformer primary and in series with each other in a manner to match the reactance of the output impedance so that the load thereon will approach unity power factor and result in a delivery of greater power to the regulating or follow-up motor. Filter condensers -18 and C-19, Fig. 7, are connected in a series relationship from the 300-volt direct current supply of rectifier V-12 to the plate supplies of tubes V- and V-6 respectively. Their function is that of smoothing out the ripple of the rectifier output.

Condensor C-20 is connected in parallel with resistors R-39 and R39A in the CT bias circuit as shown in Fig. 10. This condensor-resistor network functions to provide the proper phase shift of the control transformers bias voltage from CT.

Condensor 0-21 is connected in series with choke CH-l in the choke input filter circuit for the 600-volt rectifier. Condensors C-22, C-23 with choke CH-2 are connected across the rectified 300-volt output of tube V-12 in an inductance input filter arrangement which functions to filter or smooth out the rectifier voltage and produce a more uniform output therefrom. Condensor C-27 is connected in series with resistor R-Sl in the indexing drive control circuit across the contacts of indexing switch SW- 5 in a manner to eliminate arcing.

Condensor C-28 is connected across the output of the 230-volt rectifier as a condensor type filter. It is used in the circuit to reduce pulsation of the rectified direct current.

The circuit includes conventional resistors, designated by the prefix R. The designation series runs from R-1 to R52 inclusive. With the addition in the series of re sistors R-ZIA, R-39A, R-40A, R-43A, R-44A. The manner of connection of these resistors in the electrical circuit is hereinafter explained more fully in the description of the systems operation.

The resistors R-40, R-40A, R-41, and R42 are connected in the CT bias circuit as shown in Fig. to produce the proper voltage and phase shift in the circuit output of transformer T-7.

The resistors R-43 and R43A are connected across the output supply of the 600-volt rectifier to function as a bleeder therefrom to prevent a charge being sustained by the condenser when the system is deenergized.

Resistor R-Sl is connected in series with condenser C47 in the indexing drive control circuit in a manner whereby the network functions to eliminate any tendency toward sporadic flow of current or arcing of the contacts of the indexing switch SW-S.

Resistors RS4 and R-54A are connected in parallel across the 230-volt direct current rectifier output to serve as bleeder resistors to dissipate any charge which might be sustained by condenser C-28 when the circuit is deenergized.

The relay units of the electrical system are designated by the prefix RY for the conventional relays and RVY for the vacuum tube relay systems. Relay RY1 is a response selector relay which functions as an electrically operated switching device to control the CT error voltage during the engagement of the indexing drive. It is con nected in the indexing drive circuit of the B-unit. it functions when deenergized in a manner whereby the relay switches thereof control the CT transformers in order that the error signal from CT1 and CT-3 may be transmitted through the relay, while the signal from control transformer CT-2 is cut off at the relay. When energized, the relay-switches control the error signals from CT-l and CT-S back to CT2 as described hereinafter in the operational description.

Relay RY-Z is an electrically controlled switching device which serves as the safety circuit interlock relay. it functions when energized to open the circuit and prevent release of a projectile during the indexing drive. Alternatively it operates until the fuse setter pawls have been positively engaged by three dead turn rotations. It is electrically connected in the indexing drive control circuit to operate in conjunction with other elements as described in the description of the system operation.

Relay RY3 is an electrically controlled switching device which serves as a release circuit interlock relay to control release of the projectile. This relay is controlled by elements of RVY-1, RVY-2, RY-Z and the minimum fuse setting switch SW4 of the regulator safety circuit. These other elements are connected in series with the coil thereof. The contacts of this relay are connected in the projectile release circuit in a manner whereby the relay coil must be energized, as one of the conditions to be met, before the projectile may be released from the fuse pot.

The relay it --4 serves the system as a time delay relay. It is connected in the indexing drive control circuit in a manner to be controlled by the action of relay control switch BZ-2 at 158 for energization thereof. This relay operates in conjunction with other elements of the in- (taxing drive control circuit to control the action of the magnetic clutch and brake coils 171 and 173 respectively. When a projectile enters the fuse pot, relay RY4 coil is deenergizcd although the circuit is maintained for a short period of time through the time delay action of the shortcircuited coil thereof. The relay is designed to provide approximately 0.4 second time delay in the switching action thereof.

The vacuum tube relay RVY-l is a more accurate switching device which provides snap action for a very definite and desired voltage value or condition. It is connected in the low-speed signal vacuum tube circuit in a manner whereby it serves as a speed transfer relay. It is controlled by the low speed error signal to function in transferring control from the high-speed signal to the low-speed signal, and to open the regulator safety circuit whenever the low-speed signal is in control.

Vacuum tube relay RVY2 serves as a synchronizing relay, wherein it is connected in the high-speed signal vacuum tube relay circuit in a manner to be controlled by the high-speed signal. It functions to open the regulator safety circuit when the error voltage exceeds a predetermined value to prevent release of the projectile until such time as its fuse is properly set. This relay thus functions to indicate synchronism and to permit release of the projectile. The operation of this relay is essentially identical to that of relay RVY-l, the only difference being in the voltage sensitivity for operation thereof. The particular function of the vacuum tube relays with respect to the circuit relays is more fully described in the following description of the mode of operation of the system thereof.

The electrical switches of the system comprise seven units. This includes the switches BZ-1 and 132-2 associated with the fuse pot in a manner to be placed in an operating condition as a projectile enters the fuse pot. The fuse pot movement with projectile reception is such that starting switch 132-1 and relay control switch BZ-2 are actuated immediately and simultaneously by the translatory movement of the retract shaft which is connected to the fuse pot housing.

The master control of the system is facilitated by a switch on the gun captains control panel designated BW. it is a multiple three position manually operated switch having off, run and safe positions thereon. The system additionally comprises switches SW-4, SWS, SW-o and BER-3. Switch BBR3 is a relay operated switch connected in the 440-volt, 3-phase, 60-cycle, supply. The relay coil winding of this switch is made active whenever the switch BW is turned to either the run or safe" position. It functions to activate the MO-volt circuit to the safe signal transformer for application of a safe control voltage on the control transformers and hence on the regulating motor. Regulating motor operation provides rotation of the fuse to a safe position thereof. Energization of this relay switch BBR-3 coil is by the llS-volt, single-phase, 60-cycle supply. Additionally it closes the circuit to the transformers of the rectifiers for the 300-volt, 600-volt and 230-volt direct current sup- '17 plies, the blower motor M-3 and the indexing motor Minimum fuse setting switch SW-4 maintains a minimum fuse value on the control transformers at all times. It is associated with the output drive through cam CA-Z, as shown in Fig. 9.

The indexing switch SW- of the system at 114 is operated by the indexing cam CA4. at 111 with the switch rollers 174 thereof in alignment with the contour surfaces of the cam for actuation therefrom. The brake auxiliary cam switch SW45 at 113 is operated by the brake cam CA-la at 112 in a manner similar to that of SW-S. The combined actions of switch SW-S and switch SW45 control the indexing drive cycle by regulating the action of the magnetic clutch CM-l at 171 and magnetic brake BM-l at 173.

The locked-in synchronization between the fuze pot drive and the receiver-regulator output 74, whereby the setting dog position is correlated with the fuze signal is provided by the adjustable input coupling 24. It is arranged to positively connect the fuse pot-setter input shaft with the receiver-regulator output shaft. A vernier coupling worm at 165 is arranged in meshing engagement with the gear sleeve 175 provided in the coupling hub whereby fine adjustments may be made to synchronize the fuze setter with the receiver-regulator.

Referring now to Fig. of the drawing the input supplies, and the connections of the fuze setter electrical system with the electrical system for other elements of the turret, are shown to include the lines PS-l and PS-2 which are connections for the gun control system and function in conjunction with the projectile pawl trip circuit solenoid thereof. A 115 volt synchro supply input is indicated by the reference characters SY-l and SY-Z as they feed into the input cable. Corresponding reference is made thereto at the terminal connections to the master switch BW. The coarse signal input or l-speed signal is shown as CS as it leads into the cable and corresponding connections therefrom to the switch are similarly shown, as is the case with the fine signal control or lit-speed input indicated by the reference character PS. The 115 volt single phase 60 cycle A. C. supply which may be derived, for example, from the projectile hoist supply is shown as including the leads PS-l and PS-Z. The 3 phase, 440 volt, 60 cycle A. C. supply is shown with the respective leads thereto indicated A. -B, and -C at the separate phase terminals therefor. The three lines are suitably fuzed prior to control thereof by relay switch BER-3 which swings three contactors across the respective terminals thereof, and prior to the showing of the entrance of these leads into the 3 phase cable. The motor units M-2, and M-3 which are Y connected as 3 phase devices thereacross are respectively connected in parallel. This supply source also provides single phase taps for the power transformers T-3, T-4, and T-S as well as for the safe signal transformer T-6. The respective phase connections for these transformers are shown for T4 as being across B and C, that for transformer T-4 being -A and gb-B. The connections for transformers T-5 and T6 are in parallel across the single phase terminals -A and -C as shown.

The four secondary taps from transformer T-6 are shown respectively as 58-1, 88-2, SS-3 and 85-4 and are provided for the application of their respective safe signal voltages across the control transformer when the switch BW is turned to the safe posititon.

The coarse signal input is indicated as CS as it provides for flow to the several switch elements. The flow across the switch terminals through respective contactors thereof to the control transformer primaries is. designated by the prefix GP for the primary inputs respectively CP-l, CR4, and CP3. The fine signal input PS for application to the line control transformer (IT-3, when passed across the switch terminals is changed in designation to read F? for the fine primary connections. The coarse control output from the control transformers CT-l and GT4 is shown for the secondary of control transformer CT-l to include the secondary leads CC-l and CC-2 which are connected therefrom to terminal connections of RY-l and T-7 respectively. The secondary lead CC-3 of control transformer CT-Z is connected to a second terminal of RY-l. The fine control output indicated across FC-1 and FC-2 is derived from the fine control signal FS as applied through the control transformer CT-3 from fine primary connections PP. The lead FC-l thereof is connected to one terminal of the potentiometer P2 and to the resistor R-Il of the vacuum tube relay grid signal input for tube V-3. The second lead from the fine control transformer secondary indicated FC-2 is connected to ground.

The connections from the three control transformers, the hereinbefore mentioned 3-phase input, and the power supply input are shown for purposes of clarity of illustration as being enclosed in cables. Also the output across the output transformer T-2 of the amplifier is applied through a cable wherein the connections AM-l and AM-2 as amplified outputs are applied respectively across the control winding of the motor M-1.

The circuitry of switch BW includes an auxiliary circuit for projectile pawl release control. It includes the terminals 68-1 and GS2 which are controlled in normal fuze setting operation by action of relay RY-3. The cable for connection between terminals of switch BW and relay RY-3 additionally includes connections PS-l and PS-3 which provide current flow through signal lamps L when relay RY-3 is actuated. The power source for this lamp operation is derived from the volt, single phase, input across PS-1 and PS-Z. The light signal functions in a manner as is apparent from Fig. 8, to indicate the completion of the fuze setting operation. As RY-3 actuates the contactors to close these circuits across the terminals thereof, the projectile pawl trip circuit solenoid referenced (SAG) in Fig. 8, but not shown, is actuated to provide for projectile release and ejection thereof from the projectile cradle 12 by action of the ram spring 23. See copending application to P. H. Girouard et al., Serial No. 153,262.

The functioning of switch BW in this circuit provides for bypass of the fuze setting system when it is desired to use projectiles of a non-fuze set variety. The control by switch BW is that of closing the circuit for solenoid SAG through the terminals 68-1 and 68-2 thereof when the switch is turned to the o position thereof. The closing of the circuit through GS-1 and GS2 is accomplished by the relay RY-3 when switch BW is at either run or safe, and then only when the fuze has been set or rendered safe by the fuze system.

The several direct current supplies for the system as provided by the rectified outputs of the 600 volt, 300 volt and 230 volt power transformers T-3, T-4 and T-5 supply D. C. voltages thereto indicated respectively 13-1, 13-2 and B3 on the drawings. The additional direct current connections of the circuit which are shown on Fig. 10 as B-4 through B8 inclusive are derived from the 230 volt rectified source. These B voltages are applied to the relay coil windings, the magnetic clutch coil and the magnetic brake coil for direct current operation thereof. The designations 8-4 to 8-8 are provided for the lines thereof to permit identification of terminal connections and to permit differentiation thereof with respect to alternating current lines, synchro supply, and control transformer connections of the system.

Operation of fuze setting control system The fuze setting mechanism is placed in operation upon reception of a fuzed projectile in the cradle, as fed thereto by the hoist system of the turret.

Let it he assumed for the purpose of description that the fuze pot is engaged and the retract handle is in a position permitting engagement of the switches BZ1 19 and BZ-Z associated therewith to activate the controls of the receiver-regulator drive unit therefor.

Projectile fuze setting operations take place and are completed in the projectile cradle. The projectile nose is initially received in the holding and setting cup assembly of the fuze pot as the projectile is moved upwardly into the guide 13, of the projectile cradle assembly 2. The ram spring 23 encased by the fuzc pot housing is compressed by action of the conveyer hoist flight to provide for release of the projectile during its ramminc phase at the gun transfer trays. The fuzed projectile i2 is engaged by the fuze pot 5 and maintained in contact with the cup members by action of the projectile retaining pawl, not shown, of the cradle. The action of this projectile retaining pawl of the cradle is controlled by the solenoid designated SAG in Fig. 8 which is in the projectile pawl trip circuit of lines (-1 and (184 of Fig. 10. The function of this solenoid control will be apparent and more fully understood from the description of the operation of the system which follows.

The drive assembly, for the holding dog 14 and the setting dog 16 which are mounted in their respective holding and setting cups, is enclosed within the cradle housing as hereinbefore described in greater detail. The gearing of this drive includes a differential gear unit arranged in a manner whereby the pawls or dogs travel in mutually opposed relationship with each other upon rotation of the single input at 24. The arrangement is such that the pawls will approach each other with one direction of rotational input and separate with rotation in the opposite direction. This arrangement satisfies the condition necessary for proper representation of [tile setting angle when the device is synchronized, in accordance with control input, with the receiver regulator and the particular orientation of the pawls taken as a pair has no significance since the insertion of the projectile into the guide and fuze pot assembly is a random orientation whereby the fuze slots in the nose thereof differ positionally with each projectile insertion. However once the hcreinbefore described three-turn orientation including two dead turns, is complete, the position of the slots represented by angular separation therebetween or between the pawls of the fuze setter represent fuze setting angle when the device is in synchronization or in approximate fuze angle relation ship until synchronization is complete. After initial synchronization with the fuze setting order, the relationship of the pawls is such as to advantageously change fuzc setting order in the fuze with change of fuze setting order input from the plotting room of the ship, it thus functions to reestablish the correct synchronization relationship between the incoming signal and the l'uze angle at all times thereafter. This provides the advantage that the fuze may be set and thereafter have the setting altered or the fuze set to safe by control at switch BW while the projectile is in the cradle.

The indexing motor M-2 operates continuously although the drive output thereof is applied to the differential 116 only when the fuze holding cup is under rotation to provide engagement of the fuze holding dog with the corresponding fuze slot. The application of drive energy is through the clutch-brake combination which operates when electrically energized to release the clutch disc 99 from the braking surface 172. Simultaneously with this release action of the clutch disc 99, it is pressed against the rapidly rotating clutch surface of the motor flywheel 98. This transfer is made magnetically by D. C. coil BM1 of the brake solenoid winding 173. The cooperative action of this brake and clutch assembly is such as to provide a rigid brake action when the output is not operative and to provide a rapid energy transfer when the gearing is required to run. With the continuously operative motor there is no speed loss due to motor pickup, and the energy transfer is accomplished with satisfactory rapidity.

The drive assembly for the holding dog and the setting dog is placed in operation by positioning switch BW at ii U the run" position thereof for dog rotation to a position in engagement with a mating portion of the projectile nose. As hercinabove described, setting dog engagement with the rotatable [uze parts follows after holding dog engagement. Also the setting cup is arranged to receive sulficient rotation after holding dog engagement to prevent false synchronization at a degree out of phase condition.

The drive input to the iuzc pot gear mechanism is applied at the coupling 24 between the receiver-regulator Admit and the cradle proper. This input imparted from shaft 74, and hub 25 to the coupling hub 26 drives through a gear train 27, 3E 32, and 41 bereinbcfore described in greater detail to drive the external ring gear 42 of the lower differential gear assembly at the holding cup. This differential assembly rotates the holding cup bevel gear 45. The ring gear 42 additionally rotates the bevel spiders 43, and 44, and the upper bevel gear surface 46 of the double intermediate gear 53 located in parallelism with the holding cup gear 45 to apply rotational motion through the second bevel surface of S3 to the fixed bevel idler gears iii and 49 of the upper differential to the extreme upper bevel gear 54 which imparts the drive energy through drive 56 and shaft 57 for setting dog rotation. The showing of Fig. 3 clearly illustrates the driving arrangement when taken in consideration with the detailed description of the specific elements of the receiver-regulator drive.

The driving power for the fuze pot assembly of Figs. 2 and 3 is provided by an output or mechanical response from the receiver-regulator, or A-unit, of Fig. 5. This receiver-regulator drive is shown schematically in Fig. l. and diagrammatically in Fig. 6.

The cooperative and interussembly relationships as to function and mode of operation of the iuze setter mechanical. and electrical units are presented in diagrammatic form in Fig. 9, to facilitate a better understanding of the primary and auxiliary control actions thereof.

The power or electrical functon relationships are represented by bold flow lines with arrow indications as to direction of application. The electrical auxiliary control or power functions are represented in a similar manner by broken lines of flow. The mechanical function applications are shown in outlined bold flow lines. with secondary or auxiliary mechanical functions shown in broken outline.

The control for setting the fuzc nose to a particular fuzing value is applied to the system as a fuzc setting order from either the forward or aft plotting rooms as indicated in Figs. 1 and 9. This signal is applied through a switch of Fig. 9 in the turret officers transfer switch board. from which it is transmitted to the gun cnptains control panel through the switch BW shown in greater detail in Fig. 8. This input to the switch BW is in the nature of a connection F5 for the lit-speed and the connection CS for the l-spced inputs as well as connections SY-l and SY-2 for the llS-volt synchrosupply from the turret officers transfer switchboard applied through switch BW as hereinbefore described in greater detail with reference to the electrical schematic showing of Fig. 10. The coarse signal input CS from switch BW to the control transformer CT] of Fig. 10 is applied mechanically as shown in Fig. 6 to drive the dial DL-1 of Fig. 9. Similarly this signal CS is applied to the control transformer CT-Z whereby it produces an error voltage across CC-3 and ground which is applied through similarly designated terminal connections of the relay switch RY-l when closed to apply this voltage in opposition to the voltage on the stator windings of the generator 6-1 for damping operation prior to application of the error signal to the amplifier.

The l8-spced circuit F5 from the switch BW at its run position is applied as shown in Fig. 8 to control transformer CT-S, the output of which is applied through FC1 and FC-Z to the electronic relays RVY-1 and RVY-Z. 

